Abstract:Primulaceae,comprising 22 genera and about 1000 species, is found in almost alltemperate and subtropical parts of the world as well as in some tropical montane regions. Although the total range of the family is worldwide, most of the genera are muchmore restricted. The 22 genera may be divided into the following distribution patterns.1. Subcosmopolitan: Lysimaehia, Anagallis, Somolus.2. North temperate: Primula, Androsace, Cortusa, Trientalis, Glaux.3. West & Central Asia: Dionysia, Sredinskya.4. East Asia: Stimpsonia.5. Sino-Himalaya: Bryocarpum, Pomatosace, Omphalogramma.6. Northeastern Asia-Western North America disjunct: Dodecatheon.7. Eurasian-Eastern North America disjunct' Hottonia.8. South Europe-Mediterranean: Cyclamen, Soldanella. Asterolinon, Cons.9. Tropical Africa mountains: Ardisiandra.10. Temperate South America: Pellatiacesa.Following Takhtajan's floristic regions of the world, the number of genera and speciesin each region are counted. The statistics show that the regions in richness of number ofgenera and species are successively: Eastern Asiatic Region (561/12), Irano -Turanian Region(150/12), Circumboreal Region (118/13), Mediterranean Region (63/9), North AmericanAtlantic Region (29/8), Sudano-Zambezian Region (31/6), Indochinese Region (30/4),Madrean Region (26/8), Rocky Mountain Region (27/6), Hawaiian Region(11/1), MalesianRegion (9/4), Chile-Patagonian Region (6/3), Northeast Australian Region (6/3),Brazilian Region (5/3). But the genera and species arc not evenly distributed ina region. The family is, however, an outstanding example of widely distributed, but exhibiting endemism, with the bulk of itS species (with 70% genera and 60% species) concentratedin two distribution beltS: one stretches from western China along Himalayas, covering avery narrow (c. 240 km wide) strip of territory, to Kashimir, but at the eastern end, thebelt widens, including Yunnan, western Sichuan, Guizhou, upper Myanma and northernVietnam; the other stretches from Caucasus along Alps to Pyrenees, includingmontane regions of south Europe in the north and extending to the cost regionof Mediterranean in the South. There are 12 genera and more than 500 species in China.The greatest concentration of species and diversity appears in western China and EastHimalaya, while Caucasus-Alps-Pyrenees is the secondary present distribution centre. Because the Himalaya and Alps-Pysenees are, geologically speaking, quite new and lack ofprimitive taxa, these areas are not considered as the centre of origin. On the contrary, themost primitive subgenus Idiophyton of Lysimachia, which is often cited as an archaicmember of the Primulaceae that suggests a connection on the Myrsinaceae, and theprimitive section Samuelia of Androsace, section Carolinella and section Monocarpicae ofPrimula are all confined to southern Yunnan, Guizhou, Guangxi, northern Vietnam, Myanmaand Thailand. Although there were transgression and regression of the sea, this area neverentirely submerged again since it raised in paleozoic period. It seems reasonable to presumethat the Primulaceae was origionally evolved in the mountane region of SE China includingnorthern part of Thailand, Myanma and Vietnam. In Tertiary, some species of the threelarge genera,viz.Lysimachia, Androsaee and Primula, might be widely distributed in Eurasia.During the Pleistocene ice age, they retreated to and survived in the refuges in westernChina,Caucasus and mountains of South Europe.Later they were well developed in theseareas and spread rapidly along the mountain ranges,and the present distribution patternswere formed.In the complete absence of any fossil evidence, an accurate account of the time of originis impossible. In the three families of Primulales(Myrsinaceae,Theophrastaceae,Primulaceae)only a few fossil leaves were found in Tertiary stratum from Europe, NAmerica and Greenland. Most taxonomists agree that the three families are closely allied,and A.Cronquist pointed out that"No one family of the Primulales is likely to bedirectly ancestral to either of the others".If this point of vie

Abstract:The systematic position, evolutionary trends, modem distribution pattern, center ofdistribution and differentiation of Styracaceae are discussed. Styracaceae, comprising 11 genera, is a natural group in the Ebenales. Embryological and morphological evidences indicatethat it was most fibly evolved from Theaceae. Morphologically, the superior ovary, imbricatecorolla-lobes, stamens twice as many as corolla-lobes and inflorescences paniculate areconsidered as primitive features, while the inferior ovary, valvate corolla-lobes, stamens asmany as corolla-lobes and inflorescences with fascicled or solitary nowers, advanced features. In Styracaceae, Styrax is the largest and most diverse genus with both primitive andadvanced features. The other genera are closely ailled and seem to have a common originfrom tile Styrax stock.Floristically, six distribution patterns of the eleven genera are recognized. 1. Pantropic:Styrax, 2. Tropical Asia f Rehderodendron,Huodendron, Alniphyllum, Parastyrax, Bruinsmia,3. E. Asia and N. America disjunct:Halesia. 4. E. Asia: Pterostyrax, 5. Endemic to China: Sinojackia,Melliodendron,6.Tropical America f Pamphilia. Among the seven genera distributed to tropical areas only three actually occur in tropical regions,the others are insubtropical regions or on the fringe of it. Therefore, Styracaceae may be considered asmainly but not typically a tropical family,and originated from tropical mountains in thepast.The floristic analysis shows that there are 10 genera and 57 species(8 endemic genera,34 endemic species)in East Asia,occupying 91% and 36% of the total genera and speciesin this family respecitively.Ther are 10 genera and 54 species in China,mostly in areasfrom Qinling Mountains and Changjiang river to Naming Mountains,and S.W.China,including most primitive group (Styrax series Imbricatae)and the group of variousevolutionary stages.In tropical America there are two genera,83 species(1 endemic genera,76 endemic species),occupying 18% and 52% of the total genera and species of this familyrespectively.Although, tropical America is most rich in species, but there are only two generaand lack of primitive group. For this reason,East Asia is considered as a primary centerof the distribution of Styracaceae species,and tropical America, secondary center.According to the fossil record and modern distribution pattern of Styracaceae, the ancestor of this family maybe originated in Cathaysia flora during the Cretaceous time.

Abstract:The Chloranthaceae comprises about 68 species in four gerera,viz.Sarcandra,Chloranthus, Ascarina and Hedyosmum. Its systematic position, classification, presentdistribution, fossil records and their morphological characters are discussed. The followingconclusions have been reached: a. the establishment of the monotypic order Chloranthales isreasonable; b. the four genera of Chloranthaceae are at the same evolutionary level, c. theMalaysian region is the present distribution centre of Chloranthaceae;d.the origin of thefamily is suggested to be NW.Gondwanaland and SW.Laurasia; e.the time of origin ofthe Chloranthaceae may not be later than Barremian of the Cretaceous.

Abstract:Leaves of 134 species or infraspecific taxa,representing almost all series or subsections of thefive genera of the tribe Cercideae:Cercis,Adenolobus,Griffonea,Brenierea and Bauhinia,have beenstudied.Twenty venation types have been described.In the tribe,Adenolobus and Brenierea have very similar venation patterns.Cercis species alsohave their own characteristics.Venation of Griffonea leaf is very specialized and characteristic,while Bauhinia is very diverse in venation patterns.In the genus Bauhinia, both subgenera Bauhinia and Phanera are very diverse in aspects of leaf venation, while venation types of the two sections of Subgen. Elayuna are very similar.Theleaf venation of B.syringifolia, the only species of Subgen. Barklya, is one of the best developedvenation types and is very similar to that of Subgen. Elayuna type.The venation characters support the distinction,if not necessary being monophylies,if Ser.Cansenia,Ser.Acuminatae,Ser.Purpureae,Subsect.Viridescentes,Subsect. Tacemosae,Subgen.Elayuna,Ser.Corymbosae,Ser.Chloroxantheae,Ser.Clavatae,Sect.Palmatifolia,and Sect.Tubicalys.Like other morphological or palynological characters,leaf venational characters can be a source of inrormation for systeratics,but it can only be used in systematics together with datafrom other aspects.

Abstract:The seed of Amomum maximum Roxb. comprises aril, seed coat, perisperm,endospermand embryo.The seed coat formed from outer integument can be divided into exotesta,mesotesta and endotesta. Exotesta contains only one layer of epidermal cells withthickening and lightly lignified cell wall.The mesotesta includes hypodermis,oil cell layerand pigment layer which consists of 2-5 layers of cells. Hypodermis and oil cell layer arerespectively composed of only one layer of greatly compressed cells.The endotesta consisted ofone layer of sclerotic coils, the principal mechanical layer,is extremely thick, and nearlyoccupies one to two third of the total thickness of the seed coat.The appearance of outline of the endotesta looks like wave-shaped, except that of parts' outline of endotesta atmicropylar and chalazal ends.A micropylar collar, an operculum and a parenchymaticpart are differentiated at micropylar end. A hypodermal cell pad,large parenchyma cellgroup,vascular bundle and pigment cell group are differentiated at chalazal end.The cellso f perisperm are full of starch grains, and the cells of endosperm,except cells of its outermost layer,are abundent in proteins and polysaccharides. Cells of embryo contain pro teins,polysaccharides and lipids.Lipid is absent in oil cells,but present in embryo cells,in cells of aril adjacent to epidermis, in exotesta cells and in cells of the outer most layerof the endosperm.Because the oil cells are without lipid, they can not be called 'oil cell'anymore.The term'translucent cell' is suggested to use here instead of 'oil cell'.

Abstract:More than one pollen tube entering into one embryo sac was observed after pollinationin Apomixis parent Ⅳ,an indica rice twin seedling line.Zygotes of most embryo sacsdeveloped into normal zygotic embryos,but a few Zygotes developed into cleaved Zygoticembryos through apical cleaving of proembryos and formed seedlings, each of whichwith two plumules and one radicle.In some embryo sacs,synergid cells developed intosynergid embryos after fertilization.In some embryo sacs, without fertilization,antipodalcells directly developed into antipodal embryos.

Abstract:Explants of root,hypocotyl,cotyledon,leaf and petiole from seedlings of Melissitusruthenica L.could produce callus tissues when they were cultured on MS agar mediumcontaining 2,4-D 2-0.25mg L-l and KT 0.25-2mg L-1,or 2,4-D 0.5mg L-1 and ZT0.5mg L-1,or BAP 0.5mg L-1 and NAA 0.05mg L-1.Callus tissues Could be induced todifferentiate somatic embryos when they were transfered to MS medium containing 2,4-D0.5-0.1ing L-1 and KT 0.5-0.1mg L-1,or BAP 0.25mg L-1 and NAA 0.05mg L-1.Somatic embryos could develop into whole plants on hormone free MS medium.Somaticembryos were encapsulated by 1.5% alginate to prepare artificial seeds,of whichgermination rate and plant conversion rate were 95% and 53%, respectively.

Abstract:The dynamic characteristics of dominant populations can show forest succession process.In this paper, the dynamoic characteristics of two mesophyte populations,Cryptocaryachinensis and Cryptocarya concinna, during succession in Dinghushan were studied.The mainresults were as follows:1. The niche breadths of the two populations increased gradually in the stage of needlebroad-leaved "dxed forest.This trend stopped in the stage of territorial seasonal evergreen broad-leaved forest.2.In the process of succession,the intensities of the distribution patterns fluctuated atlow-- intensitied clumped distribution with their dispersing, developing, self--licitted functionand other ecological factors.3. The coefficients of association and niche overlap between mesophyte populations andPinus massoniana population were relatively low in the stage of needle--broad --leaved "dxedforest,and dropped to zero in the stage when the heliophytes became dominant in the evergreen broad--leaved forest. Two values between mesophyte populations and heliophytepopulations turned from high to low during the whole period.These results showed the feature of mesophyte populations as the climax populations ofthe forest.

Abstract:The paper deals with the mitigative effect of calcium on NaCl stress upon nitrogenfixation of Anabaena 7120 under different physiological conditions.The followingobservations have been made:1.The nitrogen-fixing activity of Anabaena under NaCl stress was mitigated with theincrease of calcium chloride in culture solution.Over 5×10-4 mol/L CaCl2,there was amarked weakness in mitigative effect of calcium on nitrogen-fixing activity of Anabaenaunder NaCl stress.2. Under dark condition or in the presence of photosynthetic inhibitors, such as DNPand CCCP, the mitigative effect of calcium on NaCl stress upon nitrogen fixation byAnabaena was diminished,but enhancing effect occurred when exogenous sucrose wasadded to the culture solution.3.The mitigative effect of calcium on NaCl stress upon nitrogen fixation by Anabaenaunder anaerobic condition(in Ar or N2)was lesser than that under aerobic condition.4.The addition of H2 together with O2 could accelerated nitrogen-fixing activity ofAnabaena under NaCl stress, while further depress was observed by adding oxygen alone.5.The mitigative effect of calcium on NaCl stress upon nitrogen fixation by Anabaenawas slightly enhanced to a certain degree by the preincubation of 5% CO2 or of 5% CO2 with40% N2 respectively,but was abated by the addition of N2 alone.The mitigative effect of calcium on NaCl stress upon nitrogen fixation by Anabaenaand its regulatory mechanism were discussed.

Abstract:The non-enzymic scavenger for superoxide radicals was found in leaves ofsome plants, such as mango (Mangifera indica),guava(Psidium guajava),pine(Pinusmassoniana) and green tea. The equivalent scavenging capacity for one unit of SOD activityin these plants was 0.5mg to 1.0mg of fresh weight or 0.29mg of dry tea. Heat treatment ofthe rude extract could not reduce the scavenging effect. Similar patterns onPAGE-electrophoretogram were identified either by normal NBT-SOD test or phenolicreagent(AgNO3-NH4OH), it indicated that phenolic compounds Aught be one of the maincomponents with non-enzymic scavenging effect on Moreover,some synthesizedphenolics (guaiacol,propyl gallate, p-nitrophenol)and plant digallic acid could asloscavenge the in vino.

Abstract:The fertility transformation of 12 lines of photoperiod/temperature--sensitigenie male-sterile rice(P/TGMR)in Guangzhou and their responses to variousphotoperiod and temperature treatments were studied. Experimental results showed that allvarieties possessed a sterile period at natural condition in Guangzhou, but the stability andduration of sterility were different among 7001s, N5088s, Nongken58s, 8902s, 8912s,W6154s,W8013s,Petai64s, KS-14,KS-9, W6184s and W6111s. Fertility of W6111s andW6154s was more fluctuated in the sterile period as compared with other sterile lines. Thefertility of 7001s, N5088s, Nongken58s and 8902s were higher than that of others in lateseason. Nine sterile lines showed first fertility transformation from fertility to sterility inearly season and second fertility transformation from sterility to fertility in late season.No obvious fertility transformation was observed in KS-14 during both seasons.According to the results by various photoperiod and temperature treatments, it is proposed that 700is,N5088s,8902s,Nongken58s and 8912s belonged to PGMR(photoperiodsensitive genie male sterile rice),but the degree of their fertility restoration was slightly related to temperature under short day-light.W6154s,W8013s,Petal64s and KS-14belonged to TGMR(thermasensitive genie male sterile rice), and the sensitive temperature fromsterility to fertility was different,it was 24-27℃ for W6154s and W8013s, and 21-24℃for KS-14 and Peiai 64s.

Abstract:The absorption and distribution of phosphorus in Cymbidium sinense(Andr.)Willdcultured in radioactive phosphorus(NaH2 32PO4)solution were studied.The absorbing abilityof 1-year-old root was stronger than that of 2-year-old root,but the latter still hadrather strong absorption ability, hence good care should be taken in both kinds of rootduring cultivation process.The sequence of accumulation of radioactive phosphorus(cpm/100mgDW) in vegetative groWth period was leaf bud, pseudocorm and leaf, but in reproductive growth period was floral bud, pseudocorm and leaf. This phenomenon coincideswith the rule that nutrient should distribute towards the growth center of plant.